<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>后盾人</title>
  </head>
  <body>
    <script>
      let n = 1;
      // n=n+1
      // ++n;
      // n++;
      // console.log(n);
      let f = 2;
      let d = f + n++;
      console.log(d);
    </script>
  </body>
</html>
